Hovership



Oct. 1, 1968 D. J. HARDY 3,403,652

HOVEHSHIP Filed Sept. 7, 1966 2 Sheets-Sheet 1 FIG.2

D. J. HARDY Oct. 1, 1968 HOVERSHIP 2 Sheets-Sheet 2 Filed Sept. 7, 1966 United States Patent 3,403,652 HOVERSHIP Derek James Hardy, Cowes, Isle of Wight, England, assignor to Westland Aircraft Limited, Yeovil, England Filed Sept. 7, 1966, Ser. No. 577,732 Claims priority, application Great Britain, Sept. 24, 1965, 40,884/ 65 2 Claims. (Cl. 114-435) ABSTRACT OF THE DISCLOSURE A composite vessel includes at least two portions, one of the portions comprising a powered displacement vessel having at least two hulls spaced apart and joined together by structure, part of the structure forming a docking area, and the other portion comprising an air cushion vehicle adapted to be housed within the docking area and separable from the powered displacement portion when desired. The upper after surfaces of the bulls and the upper after surface of the joining structure cooperate to form a substantially fiat deck which is boundaried, at least in part, by side and rear peripheral walls extending above the deck. The side and rear peripheral walls are hingedly attached to the vessel to allow outward and downward pivotal movement thereof during launching and recovery of the air cushion vehicle, and wedge shaped guidance members located on the inner surfaces of the side walls for progressively restricting lateral movement of the air cushion vehicle as the vertical distance between the base of the air cushion vehicle and the deck decreases when the air cushion vehicle is settling onto the deck during recovery operations.

This invention relates to sea-going vessels, which includes vessels operating on large lakes and inland seas, and is specially concerned with the design features of a composite vessel having two or more operationally separable but complementary portions. One of these portions is preferably a true displacement vessel, and is the larger. The others are air cushion vehicles which can be either cushionborne or waterborne, according to the immediate requirements.

The composite vessel, in which each part may operate in co-operation with the other even when separated, is primarily intended to play the role of a fighting ship in anti-submarine warfare, but need not, of course, be limited to such a role, and it is an object of the invention to combine the advantages of an air cushion vehicle with those of a displacement vessel, without going to the extreme of building the very large and expensive hovership that would be necessary to attain the required speed as a displacement craft, and to enable such a vessel to remain at sea for long periods in all Weathers. Conventional single-hulled vessels having stern doors in the known manner of, for example, whaling ships or ferry craft, have been considered, to act as parent craft for the proposed composite vessel, but such a single-hulled vessel could not have been suitably constructed with the large open well deck area necessary for the requirements of the present invention, whilst still providing adequate stability.

It was with the problem of combining the advantageous characteristics of both the displacement vessel and the air cushion vehicle in one vessel in mind that the present invention, which provides a vessel especially adapted to receive air cushion vehicles from the sea and to house them in the dock area, was evolved.

According to the invention, we provide a composite vessel including a displacement portion having at least two hulls and at least one separate air cushion supported portion, the portions being arranged to act as one operational unit, the displacement portion having the capability of carrying the air cushion supported portion.

In another aspect of the invention, we provide a composite vessel including at least two portions, one of said portions comprising a powered displacement vessel having at least two hulls spaced apart and joined together by structure, part of said structure forming a docking area, and the other portion comprising at least one air cushion vehicle adapted to be housed within the docking area, and separable from the powered displacement portion, when desired.

According to a further aspect of the invention, each portion of the composite vessel may be provided with at least partial air cushion support.

The invention will be described with reference to the accompanying drawings, which are by way of example, and in which:

FIGURE 1 is a perspective view of a composite vessel in accordance with a preferred embodiment of the invention,

FIGURE 2 is a composite vertical diagrammatic crosssection, in planes parallel to its lateral axis, of a vehicle similar to that illustrated in FIGURE 1. The right side of the figure is a section across the docking area of the vessel, and the left side of the figure is a section across the vessel ahead of the docking area, and

FIGURE 3 is a perspective view of the separate portions of a composite vessel illustrating a method by which the air cushion portion may be drawn into the docking area of the displacement portion.

In carrying the invention into effect, according to a preferred embodiment, we provide a composite vessel consisting of two independent portions. The larger portion consists of a displacement watercraft 1, hereinafter referred to as the parent vessel, having two hulls 2 and being approximately 350 feet in length with a beam of approximately feet. This portion is propelled by water propellers driven by engines and transmission shafts housed in each hull in the manner usual for displacement vessels. The hulls 2 are joined and spaced apart by structure 13 arranged so that it is always above the water line 11. The forward part of each hull and of the joining structure 13 provides space for the control rooms, crews quarters and other facilities necessary for a vessel engaged in anti-submarine activities, and superstructures may be provided above the forward parts of the hulls in which navigational and other equipment for operating the vessel is housed.

Aft of the operational and domestic areas the upper surfaces of the hulls and the structure joining the two hulls are arranged to form a substantially flat deck surface. This flat deck is surrounded by side walls 7, a stern wall 8, and, at the front, by the wall 4 of the previously mentioned operational and domestic areas, to form a dock 3.

The stern part of each hull 2 is provided with ballast tanks (not shown), which may be flooded so that the attitude of the parent vessel may be varied. For launching and recovery operations the vessel is trimmed stern down, as illustrated in FIGURE 3.

The forward end 4 of the dock 3 is appropriately shaped to receive the bow of an air cushion vehicle 5, which comprises the other portion of the composite vessel. The flat deck of the clock has support pads 6 arranged to cooperate with the landing pads of the air cushion vehicle 5, to provide support for the vehicle when it is not cushionborne. These support pads 6 are provided with jacking means (not shown) so that the vehicle can be raised, for example, for maintenance purposes.

The side walls 7 of the dock 3 have sufiicient height to afiord protection to and security for the air cushion vehicle 5, when housed in the dock 3. These walls 7 are arranged to co-operate with the sides of the air cushion vehicle 5 and are made adjustable being capable of splaying outwards vertically to approximately 45, as illustrated in FIGURES 2. and 3, during launching and recovery operations. Similarly, the stern wall 8 can be pivoted outwards and downwards to an extent sufiicicnt to form a ramp leading from the water surface to the deck of the dock when the vessel 1 is in the stern down attitude.

A movable winch 10, arranged to travel along a track 12, positioned on the longitudinal centre line of the dock 3 is provided with means to haul the air cushion vehicle 5 close to the stern of the parent vessel 1 and with traction means so that it may move, with the air cushion vehicle 5 attached, between the stern and the forward end of the clock 3. To allow the air cushion vehicle 5 to be positioned close to the forward wall 4 of the dock 3, a recess 9 is provided in the wall 4, to house the winch.

The side walls 7 have fitted to them guidance means, consisting, for example, of wedge shaped members 7a (see FIGURES 2 and 3) adjacent to the air cushion vehicle arranged so that the widest part of the wedge is uppermost, which, when the walls 7 are in their upright position, co-operate with fittings on the air cushion vehicle 5, for example, retractable spigots (not shown), so that, as the distance between the :base of the air cushion vehicle 5 and the deck of the dock 3 decreases when the air supply to the cushions ceases, or the support pads 6 are lowered, the air cushion vehicle 5 is progessively restricted in its lateral and longitudinal movement. When the distance has decreased so that the air cushion vehicle 5 is supported by its landing pads on the support pads 6, automatic locking devices for example, spring-loaded pawls (not shown) in the lower parts of the wedge shaped members 7a, engage the spigots on the air cushion vehicle '5, and secure the air cushion vehicle in a pre-selected position.

In another aspect of the invention, the tunnel formed between the underside of the joining structure 13, the two hull-s 2, and the surface of the water 11 is provided, at its front and rear, with pendulum flaps or obturator members (not shown), similar to those described in British Patents Nos. 935,531 and 1,001,059, hinged to the underside of the joining structure 13, so as to close each end of the tunnel. The space thus formed can be filled with pressurised gaseous fluid, in order to reduce the draught of the displacement watercraft, and hence the power required for its propulsion.

In operation of the invention, the composite vessel can venture into open sea as one ship, the air cushion portion being clamped and held by the adjustable walls and any other means necessary to secure it. In this condition, the vessel operates submarine search equipment, for example, by towing sonar-buoys, and generally operates as a mobile war headquarters, utilising the facilities of the air cushion vehicle as desired.

As and when required, the air cushion vehicle is launched to make a high-speed dash to a specified target area within the range of the air cushion vehicle or to patrol for a considerable period, using the facilities of the air cushion vehicle.

When the air cushion vehicle returns to the parent vessel the stern wall 8 is lowered, the sides 7 are opened out, and the stern of the parent vessel is trimmed down by flooding the ballast tanks. If weather and other conditions are suitable, a direct run-in to the dock can be made by the air cushion vehicle. As soon as the air cushion vehicle reaches the correct position on the dock 3, the sides 7 of the parent vessel are moved to the vertical position and the wedge-shaped members 7a on the walls engage the spigots on the sides of the air cushion vehicle. The air cushion generating power is now cut, allowing the vehicle 5 to settle down on its landing pads, when spring-loaded catches automatically clamp the air cushion vehicle to the parent vessel. The stern wall 8 is now raised and the ballast tanks are blown, bringing the composite vessel to a level trim.

In rough weather or at other times when it may not be possible to drive the air cushion vehicle 5 centrally into the dock 3, a line is fired from the air cushion vehicle and connected to the winch 10, which has previously been positioned at the stern of the dock. The air cushion vehicle is next hauled up to the winch, and then the winch is moved forward, taking with it the air cushion vehicle. The short scope on the cable between the winch and the air cushion vehicle holds the latter central as it is moved into the dock. Once the air cushion vehicle 5 is correctly positioned the sides 7 of the dock are raised, and the settling down and clamping procedure described above is followed.

Launching is achieved by trimming down the stern of the paren vessel and lowering the side and stern walls, when the air cushion vehicle may back out under its own power and control. The forward speed of the parent vessel is adjusted, to ensure that the air cushion vehicle has at least a small forward velocity relatively to the water as it leaves. Alternatively, if conditions make it necessary, the above described winching procedure may be reversed, and the cable slipped, when the bow of the air cushion vehicle is clear of the parent vessel.

It will be appreciated that many modifications are possible without departing from the scope of the invention. For example, a larger parent ship of similar design could accommodate two or more air cushion vehicles fore and aft or abreast of each other. Once they were aboard the parent ship they could be covered with a detachable structure or flexible sheets, for weatherproofing or camouflage purposes. Moreover, the composite vessel hereinbefore described need not be limited to any one role, and could be used as a support craft in landing operations, or as a ferry craft, when the air cushion vehicle would be used to collect passengers from a number of dispersed areas, and bring them to the parent ship standing off-shore.

I claim as my invention:

1. A composite vessel including at least two portions, one of said portions comprising a powered displacement vessel having at least two hulls spaced apart and joined together by structure, the aft part of said structure forming a docking area, and the other portion comprising an air cu-shi'on vehicle adapted to be housed within the docking area and separable from the powered displacement portion when desired, the upper after surfaces of the said hulls and the upper after surface of the joining structure cooperating to form a substantially flat unobstructed deck, said deck being boundaried, at least in part, by side and rear peripheral walls extending above said deck, said side and rear peripheral walls being hingedly attached to the vessel toallow outward and downward pivotal movement thereof during launching and recovery of the air cushion vehicle guidance means on the inner surfaces of said side walls for, when the side walls are in their upright positions, automatically progressively restricting lateral movement of said air cushion vehicle as the vertical distance between the base of the air cushion vehicle and the said deck decreases when the air cushion vehicle is settling onto said deck during recovery operations.

5 2. A composite vessel as claimed in claim 1 wherein said guidance means comprise oppositely disposed wedge shaped members arranged on the opposite side walls so that the widest distance between oppositely disposed wedges is uppermost, and the distance between oppositely disposed wedges progressively decreases so as to be at a minimum adjacent said deck.

References Cited UNITED STATES PATENTS 3,066,753 12/1962 Hurley et a1 244-51 X 1,013,087 12/1911 Couvrette 114-43.5

3/1945 Reedy 11443.5 8/ 1946 Creed 11443.5 9/ 1965 Smith 114-67 7/ 1966 Veldhuizen et a1. 115-15 OTHER REFERENCES Air-cushion vehicles supplement to flight international, July 19, 1962. Iliffe Transport Publications Ltd., London, England. 1962. Copy in group 310.

10 MILTON BUCHLER, Primary Examiner.

T. MAJOR, Assistant Examiner. 

